package XPath;

import java.io.IOException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

public class DomXPath {

	public static void main(String[] args) {
		
		try {
			DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
		    DocumentBuilder builder = factory.newDocumentBuilder();
		    Document documrnt = builder.parse("sample.xml");
		    
		    XPath xpath = XPathFactory.newInstance().newXPath();
		    XPathExpression xpe = xpath.compile("//student[./gender='male']");
		    
		    NodeList list = (NodeList)xpe.evaluate(documrnt, XPathConstants.NODESET);
		    
		    for(int index = 0; index < list.getLength(); index++) {
		    	Node node = list.item(index);
		    	String id = node.getAttributes().getNamedItem("id").getNodeValue();
		    	System.out.println("Student id: " + id);
		    	
		    	NodeList childNodes = node.getChildNodes();
		    	for(int i = 0; i < childNodes.getLength(); i++) {
		    		Node childNode = childNodes.item(i);
		    		
		    		if(childNode.getNodeType() != Node.ELEMENT_NODE) continue;
		    		
		    		String nodeName = childNode.getNodeName();
		    		String nodeValue = childNode.getFirstChild().getNodeValue();
		    		
		    		System.out.println("node: " + nodeName + " = " + nodeValue);
		    	}
		    }
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (XPathExpressionException e) {
			e.printStackTrace();
		}

	}

}
